MCQ Detailed View

The given reaction is an example of the Wurtz reaction, a classical organic reaction used to prepare alkanes from alkyl halides. In this reaction, two alkyl halide molecules react with metallic sodium in the presence of dry ether to form a higher alkane. The general reaction can be written as:

2 R–X + 2 Na → R–R + 2 NaX
(where R = alkyl group, X = halogen)

In the given case, the alkyl halide is ethyl chloride (C₂H₅Cl). When two moles of ethyl chloride react with two moles of sodium metal in dry ether, the sodium removes the chlorine atoms, and the two ethyl groups join together to form butane (C₄H₁₀). The byproduct is sodium chloride.

Equation:
2 C₂H₅Cl + 2 Na → C₄H₁₀ + 2 NaCl

Thus, one mole of butane is formed from two moles of ethyl chloride.

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  Option A (2 moles of ethane): Incorrect, because ethane is not produced in the Wurtz reaction of ethyl chloride.

  
  


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  Option B (1 mole of ethane): Incorrect, since the product is not ethane.

  
  


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  Option C (2 moles of butane): Incorrect, because the stoichiometry gives only 1 mole of butane.

  
  


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  Option D (1 mole of butane): Correct, as shown by the balanced equation.

  
  

This reaction is especially useful in synthesizing symmetrical alkanes (with even carbon numbers). However, when applied to dissimilar alkyl halides, the product mixture becomes complex.